One of the many things I'm afraid of is the existence of lasers that cause permanent blindness. I know that it would take a lot of energy to melt someone's face or cut off limbs like in Star Wars, but the idea of simply shining a light at someone to the point that they can no longer see, forever, seems way more possible/plausible to me. I can imagine battlefields of the future where soldiers on both sides are afraid to look out beyond no man's land for fear of never being able to look again. Luckily, it seems like no one has built a gun specifically for this purpose.
That said, I want to know how.
So that's what I'm asking: can you create a gun that shoots permanent blindness lasers, and if so, what do/would you need? For some parameters, let's say it's effective at 50 meters, on unshielded targets that are looking directly at the gun. It should work fast enough to not be foiled by blinking. Aside from that, I'd appreciate optimization to size, range, accuracy, and acceptable deviation angle of target's field of view.